TedTalk: In clear, nontechnical language, string theorist Brian Greene explains how our understanding of the universe has evolved from Einstein's notions of gravity and space-time to superstring theory, where minuscule strands of energy vibrating in 11 dimensions create every particle and force in the universe. (This mind-bending theory may soon be put to the test at the Large Hadron Collider in Geneva.) Visit the TED conferences web site at www.ted.com.

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